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Are foreign keys really necessary in a database design?
... know, foreign keys (FK) are used to aid the programmer to manipulate data in the correct way. Suppose a programmer is actually doing this in the right manner already, then do we really need the concept of foreign keys?
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How to check whether a string contains a substring in Ruby
I have a string variable with content:
9 Answers
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Get list of all routes defined in the Flask app
... There are lots of separate files with view functions. Their URLs are defined with the @app.route('/...') decorator. Is there a way to get a list of all the routes that have been declared throughout my app? Perhaps there is some method I can call on the app object?
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Adding a column to an existing table in a Rails migration
...Users model which needs an :email column (I forgot to add that column during the initial scaffold).
11 Answers
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How do I limit task tags to current project in Eclipse?
...( // TODO ) from all open projects. I would be grateful if anyone could point out the preference, where I could restrict the scope of tasks displayed (e.g. only tasks from current project).
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Determine if 2 lists have the same elements, regardless of order? [duplicate]
Sorry for the simple question, but I'm having a hard time finding the answer.
4 Answers
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Undefined symbols for architecture armv7
This problem has been driving me crazy, and I can't work out how to fix it...
40 Answers
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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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What does the Ellipsis object do?
While idly surfing the namespace I noticed an odd looking object called Ellipsis , it does not seem to be or do anything special, but it's a globally available builtin.
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Proper way to renew distribution certificate for iOS
My distribution certificate is expiring on June 7th, along with all of my provisioning files. How do I properly renew it? Should I revoke it now and request a new one? If I do that than will all my live apps be taken down?
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